# A026651 (b-file synthesized from sequence entry) 2 1 3 9 4 40 5 240 6 915 7 5103 8 18704 9 101952 10 368490 11 1990890 12 7154928 13 38514528 14 138086403 15 742202055 16 2658662560 17 14283407616 18 51156225342 19 274842096462 20 984532674800 21 5291030979360 22 18960255044654 23 101937273452454 24 365451691152864